This navigation aid device comprises, in particular, a flight management system, for example of FMS type, which comprises usual flight management means which supply information intended, in particular, for the in-flight navigation of the aircraft. This flight management system is primarily designed for the management of the aircraft in flight, and in particular in-flight navigation.
Moreover, regarding airport navigation, that is, the movement on the ground of an airplane at an airport, independent airport navigation aid means are known, of OANS (“On-board Airport Navigation System”) type, which provide information to the crew to assist it when navigating on the ground at the airport, between landing and the final destination position at the airport or between the departure position at the airport and take-off. Such airport navigation aid means can, in particular, provide video images intended for airport map displays. Generally, the display of such a function is produced in video mode through a video concentrator of CMV (“Concentrator Multiplexer Video”) type.
Consequently, there is a difficulty, with a usual architecture of this type, for the navigation to be performed continually between the in-flight phases and ground phases. In particular, the symbol system relating to the flight management system is managed separately from the symbol system relating to the airport navigation aid means, because the latter symbol system corresponds to a video layer, which means that the corresponding data cannot be mixed, only overlaid.
For example, when producing a display, in particular on a navigation screen of ND (“Navigation Display”) type, relating to airport data, data relating to the flight plan derived from the flight management system can be displayed only in overlay mode, and it is impossible to manage the priorities for displaying certain messages that are considered more important.
Furthermore, the airport navigation aid means use navigation data that are stored in a specific navigation data base, which is itself stored in a memory of MMC (“Mass Memory Card”) type. This navigation data base (and its management) is completely independent of the data base used by the flight management system. Also, identical information which must be stored in both data bases, such as information indicating the position of the threshold of a landing runway for example, must necessarily be duplicated.
From documents FR-2 884 020 and FR-2 883 984, airport navigation aid devices are known.